A couple of blockbuster trades. A record free-agent signing. Smart tinkering here and there.

When teams with expectations don’t win the World Series, there are normally big attempts to improve chances for the next season. This offseason showed several teams doing exactly that, and a few of them have done it in a major way.

Whether it’s a good team teetering on great, a so-so team becoming a contender or a doormat transforming into a threat, this winter has already had a little bit of everything when it comes to ways to improve a roster.

Toronto Blue Jays

This is definitely the team that has improved most since the end of the World Series, and they didn’t waste much time doing it. In mid-November the Jays worked out the biggest trade in franchise history in terms of quality of players and money when they acquired Jose Reyes, Mark Buehrle, Josh Johnson, John Buck and Emilio Bonifacio and a couple of others from the Miami Marlins. In all, the Jays took on about $165 million in new salary.

Toronto finished 73-89 last season, but the trade gives them a dynamic leadoff hitter and shortstop in Reyes, two front-line pitchers in Buehrle and Johnson (if healthy) and Bonifacio gives them a speedy infield/outfield option to slot in behind Reyes. The team also went out and added outfielder Melky Cabrera on a two-year deal.

This team is surely improved and even the betting odds reflect that as the Jays have made the biggest leap in that category, going from 35-1 odds before the trade to 10-1 currently, according to Kevin Bradley, sports book manager for Bovada.lv. Those odds are behind only the Detroit Tigers, Washington Nationals and Los Angeles Dodgers.

Regardless of what sports books list, the Jays are improved, especially when you consider where they were at the end of last season.

Los Angeles Dodgers

This improvement movement started last July, continued through August and came to an apex Tuesday when the Dodgers introduced right-hander Zack Greinke at Dodger Stadium.

Besides the money and years ($147 million over six), Greinke said the main thing that attracted him to the Dodgers was, “a team that had a chance to win a World Series for several years.”

With all their additions and with the two key pieces they already had in place – Matt Kemp and Clayton Kershaw, who are still the team’s best players despite all the adds – the Dodgers have turned themselves into perennial contenders. And even though this list deals strictly with the offseason, Greinke’s signing is enough to butt them up against the Jays for the most improved team through the winter meetings.

One of the other effects of Greinke signing with the Dodgers is that it sort of weakened the Texas Rangers. Even though the Rangers never had Greinke in their rotation, whichever team he signed with was going to be vastly improved despite Greinke not being seen as a true ace. He is still a top-of-the-rotation pitcher and had the Rangers been able to sign him, they might have been the easy favorites in the American League once again.

Instead, his acquisition makes the Dodgers the team to beat in the NL West along with the defending World Series champion San Francisco Giants.

Kansas City Royals

The debate raged for about 18 hours from Sunday night to Monday evening. Was trading four prospects, including top prospect Wil Myers, for James Shields and Wade Davis a smart move for the future of the Royals? In the immediate future, absolutely. Long-term? We’ll see.

For next season, it improves them a bunch. Sticking Shields at the front of the rotation and hopefully being able to use Davis as a productive starter makes the Royals a threat in the AL Central. Bradley even pushed them from 100-1 odds to 40-1 after the deal.

However, the Royals still don’t score runs or get on base enough to be considered good offensively. They also lost 90 games last season, and Shields and Davis alone don’t make them anything close to a playoff team. Because of that, critics of the trade have plenty of ammunition.

But, the Royals are improved and shouldn’t lose 90 games again.

Boston Red Sox

To this point the Red Sox haven’t made a huge free-agent signing, but they’ve made plenty of second-tier moves. They’ve re-signed David Ortiz and added Jonny Gomes, Mike Napoli (although a Fox Sports.com report speculated that deal may be in jeopardy), Shane Victorino, Koji Uehara and David Ross. And the Red Sox might not be done as they are in on Ryan Dempster, and possibly Kyle Lohse, Josh Hamilton and Nick Swisher.

The Red Sox were about the most disappointing team in the majors last season, losing 93 games and finishing 26 behind the division-winning New York Yankees. These moves, along with ousting Bobby Valentine from the manager’s office, likely assure the team won’t lose that much next season.

Whether or not they can actually contend in the division depends on the pitching and if they can add to the rotation. However, they are surely improved to the point where they are once again a threat.